Hot spot layout correction method, device and equipment in mask layout and storage medium

Abstract

The present application relates to the technical field of mask lithography, and discloses a hot spot layout correction method, device and equipment in a mask layout and a storage medium, the hot spot layout correction method comprises determining a hot spot layout in an initial mask layout; determining the environmental graphic parameters of each contour edge segment in the hot spot layout; constructing a basic optimization objective function according to the edge placement error varying with the displacement amount of the contour edge segment; superimposing an optimization compensation term on the basic optimization objective function according to each environmental graphic parameter to obtain an optimization objective function; optimizing the displacement amount of each contour edge segment according to the optimization objective function to obtain the corrected displacement amount corresponding to each contour edge segment, so as to determine the corrected layout of the hot spot layout. The present application realizes the automatic correction of the hot spot layout without manual operation, improves the correction efficiency of the hot spot layout, and ensures the accuracy and reliability of the correction result.

Description

Technical Field

[0001] This invention relates to the field of photomask technology, and in particular to a method, apparatus, device, and computer-readable storage medium for hotspot pattern correction in a photomask. Background Technology

[0002] Optical Proximity Correction (OPC) is a technique that uses computer simulation and correction of photomask patterns to compensate for imaging deviations caused by light source diffraction and interference, thereby ensuring that the mask exposure pattern formed on a semiconductor wafer accurately meets the design objectives.

[0003] Due to the diversity of design layout topology and the nonlinearity of optical interactions, certain specific layout areas in photolithography mask layouts are prone to forming so-called "hotspots". For example, small spacing between adjacent patterns, small linewidth, large differences in pattern density on both sides or spacing between adjacent patterns can all cause local hotspot areas in the mask layout.

[0004] The layout structure of hot spots in photomask patterns is often difficult to correct effectively using conventional methods, thus posing a direct threat to the yield and reliability of chips exposed based on the photomask layout. Currently, the common approach is to manually identify and select hot spots after an initial global correction of the photomask layout, and then implement customized adjustments and secondary corrections. This manual method cannot guarantee accurate correction of all hot spots, and requires repeated debugging after correction, which is time-consuming, labor-intensive, and has a long correction cycle.

[0005] Therefore, how to accurately and efficiently correct the hot spots in the mask layout is one of the technical problems that the industry needs to solve. Summary of the Invention

[0006] The purpose of this invention is to provide a method, apparatus, device, and computer-readable storage medium for hot spot pattern correction in a mask pattern, which can achieve accurate and efficient correction of hot spot areas in the mask pattern, thereby improving the precision of semiconductor lithography.

[0007] To solve the above technical problems, the present invention provides a method for hotspot layout correction in a mask layout, comprising:

[0008] Determine the hotspot layout in the initial mask layout;

[0009] Based on the graphic information of the hotspot map, determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map;

[0010] Based on the edge placement error that varies with the displacement of the contour edge segment, a basic optimization objective function is constructed with the displacement of the contour edge segment as the variable.

[0011] Based on the environmental graphical parameters, the optimization compensation terms are determined, and the optimization compensation terms are superimposed with the basic optimization objective function to obtain the optimization objective function.

[0012] The displacement of each contour edge segment is optimized according to the optimization objective function to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective, so as to determine the corrected layout of the hotspot layout.

[0013] In an optional embodiment of the present invention, determining the environmental graphic parameters corresponding to each contour edge segment in the hotspot map based on the graphic information of the hotspot map includes:

[0014] The similarity between the hotspot map and the pre-stored sample hotspot map is calculated to obtain the maximum similarity among all similarity values.

[0015] Determine whether the maximum similarity is greater than a set similarity threshold;

[0016] If so, the sample environment graphic parameters of the sample hotspot map corresponding to the maximum similarity are used as the environment graphic parameters corresponding to each contour edge segment of the hotspot map.

[0017] If not, then the environmental graphic parameters of each contour edge segment are calculated based on the graphic information of the hotspot map, and the hotspot map and the corresponding environmental graphic parameters are stored in the database as new sample hotspot maps and corresponding sample environmental graphic parameters; wherein, the environmental graphic parameters include at least one of the following parameters: side spacing difference, single-side spacing contrast, line width uniformity, and side density difference.

[0018] In an optional embodiment of the present invention, determining the environmental graphic parameters corresponding to each contour edge segment in the hotspot map based on the graphic information of the hotspot map includes:

[0019] Based on the graphic information of the hotspot map and the first parameter formula The difference in the distance between the two sides corresponding to each contour edge segment is obtained; wherein, For the first The difference in spacing between the two sides of the segment outline edge segment. For the first The vertical distances between the edge segment of the outline and its left and right nearest neighbor figures, respectively;

[0020] Based on the graphic information of the hotspot map and the second parameter formula To obtain the single-sided spacing contrast corresponding to each contour edge segment; wherein, For the first The contrast of the spacing between the two sides of the segment outline edge segment. For the first The vertical distance between the edge segment of the segment outline and its nearest neighboring shape;

[0021] Based on the graphic information of the hotspot map and the third parameter formula To obtain the linewidth uniformity corresponding to each of the contour edge segments; wherein, For the first Uniformity of line width of segment outline edge segments For the first The line width value between the edge segment of the profile segment and the edge segment of the opposite profile segment;

[0022] Based on the graphic information of the hotspot map and the fourth parameter formula The density difference between the two sides corresponding to each contour edge segment is obtained; wherein, For the first Density difference between the two sides of the segment outline edge segment To respectively along the first The left and right nearest neighbor graphic densities are set within the area range along the normal direction on both sides of the segment outline edge. To set non-zero positive numbers.

[0023] In an optional embodiment of the present invention, a basic optimization objective function is constructed based on the edge placement error that varies with the displacement of the contour edge segment, using the displacement of the contour edge segment as the variable. This function includes:

[0024] The basic optimization objective function is constructed as follows: ;in, and The first The deviation function between the imaging position and the target position of the segment contour edge segment under nominal process conditions and preset worst process conditions; For the first The displacement corresponding to the edge segment of the segment contour. This represents the total number of all contour edge segments in the hotspot map; All are proportional parameters, satisfying ,and .

[0025] In an optional embodiment of the present invention, an optimization compensation term is determined based on each of the environmental graphical parameters, and the optimization compensation term and a basic optimization objective function are superimposed to obtain an optimization objective function, including:

[0026] Based on the environmental graphic parameters and the set anomaly threshold, a first set of contour edge segments consisting of contour edge segments with abnormal spacing difference on both sides, a second set of contour edge segments consisting of contour edge segments with abnormal spacing contrast on one side, a third set of contour edge segments consisting of contour edge segments with abnormal line width uniformity, and a fourth set of contour edge segments consisting of contour edge segments with abnormal density difference on both sides are determined.

[0027] Based on the first set of contour edge segments and the spacing balance formula Determine the spacing balance term; among which, For the spacing balance term, As the first weight parameter, This represents the total number of contour edge segments on the near-spacing side in the first set of contour edge segments. The sequence number of each contour edge segment on the near-spacing side in the first contour edge segment set; This represents the total number of contour edge segments on the far-spaced side in the first set of contour edge segments. The sequence number of the contour edge segment on the far side in the first set of contour edge segments; To set the magnification factor;

[0028] Based on the second contour edge segment set and the formula for cooperative variation term Determine the cooperative variation terms; among which, For the aforementioned cooperative change term, This is the second weighting parameter. This represents the total number of contour edge segments in the second set of contour edge segments. This refers to the sequence number of the contour edge segment in the second contour edge segment set;

[0029] According to the third contour edge segment set and width protection formula Define the width protection item; among which, For the width protection item, As the third weighting parameter, The total number of contour edge segments in the third contour edge segment set. The sequence number of the contour edge segment in the third contour edge segment set. To adjust the parameters and satisfy , ;

[0030] Based on the formula for the fourth contour edge segment set and density equalization term Determine the density equilibrium term; among which, For the density balance term, This is the fourth weighting parameter. The total number of low-density side contour edge segments in the fourth contour edge segment set. The sequence number of the low-density side contour edge segment in the fourth contour edge segment set; The total number of high-density side contour edge segments in the fourth contour edge segment set. The sequence number of the high-density side contour edge segment in the fourth contour edge segment set; These are constant parameters;

[0031] Based on the basic optimization objective function, and using the spacing balance term, the cooperative change term, the width protection term, and the density balance term as optimization compensation terms, the optimization objective function is constructed as follows: ;in, To optimize the calculated value of the objective function, Let be the basic optimization objective function.

[0032] In an optional embodiment of the present invention, the displacement of each contour edge segment is optimized according to the optimization objective function to obtain the corrected displacement corresponding to each contour edge segment such that the calculated value of the optimization objective function reaches the optimization objective, thereby determining the corrected layout of the hotspot map, including:

[0033] With the constraints that the displacement is within a set displacement range, and the spacing parameter corresponding to each contour edge segment is not less than the minimum spacing, and the corresponding line width parameter is not less than the minimum line width, the displacement of each contour edge segment is optimized iteratively to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective.

[0034] In an optional embodiment of the present invention, after determining the revised hotspot map, the method further includes:

[0035] The corrected pattern is subjected to exposure simulation to obtain a simulated exposure pattern;

[0036] The consistency between the simulated exposure pattern and the hotspot pattern is verified. If the verification fails, the weighting coefficients of each item of the optimization objective function corresponding to each contour edge segment are adjusted, and the correction displacement corresponding to each contour edge segment is re-determined according to the updated optimization objective function to obtain the corrected pattern of the updated hotspot pattern.

[0037] A hotspot layout correction device in a mask layout includes:

[0038] The hotspot determination module is used to determine the hotspot layout in the initial mask layout.

[0039] The parameter calculation module is used to determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map based on the graphic information of the hotspot map.

[0040] The function construction module is used to construct a basic optimization objective function with the displacement of the contour edge segment as the variable, based on the edge placement error that varies with the displacement of the contour edge segment.

[0041] The function adjustment module is used to determine the optimization compensation term based on each of the environmental graphical parameters, and to superimpose the optimization compensation term and the basic optimization objective function to obtain the optimization objective function.

[0042] An optimization calculation module is used to optimize the displacement of each contour edge segment according to the optimization objective function, and obtain the corrected displacement corresponding to each contour edge segment so that the calculated value of the optimization objective function reaches the optimization objective, so as to determine the corrected layout of the hotspot layout.

[0043] A hotspot layout correction device in a mask layout includes:

[0044] Memory, used to store computer programs;

[0045] A processor for executing the computer program to implement the steps of the hotspot layout correction method in the mask layout as described in any of the preceding claims.

[0046] A computer-readable storage medium storing a computer program that is executed to implement the steps of the hotspot layout correction method in a mask layout as described in any of the preceding claims.

[0047] This invention provides a method, apparatus, device, and computer-readable storage medium for hotspot pattern correction in a mask layout. The method includes: determining a hotspot pattern in an initial mask layout; determining environmental graphic parameters corresponding to each contour edge segment in the hotspot pattern based on the graphic information of the hotspot pattern; constructing a basic optimization objective function with the displacement of the contour edge segments as the variable, based on the edge placement error that varies with the displacement of the contour edge segments; determining optimization compensation terms based on each environmental graphic parameter; superimposing the optimization compensation terms and the basic optimization objective function to obtain an optimization objective function; and optimizing the displacement of each contour edge segment according to the optimization objective function to obtain the corrected displacement of each contour edge segment that makes the calculated value of the optimization objective function reach the optimization target, thereby determining the corrected hotspot pattern.

[0048] This invention is based on the principle that hotspots in a mask layout arise from the unique relative dimensions between certain graphic contours and adjacent graphics. During the correction of hotspots in the mask layout, environmental graphic parameters characterizing the relative dimensions between each contour edge segment and adjacent graphics are determined. A basic optimization objective function is constructed based on the edge placement error that varies with displacement. Furthermore, optimization compensation terms are added to the baseline optimization objective function based on the environmental graphic parameters corresponding to each contour edge segment. This ensures that the final optimization objective function simultaneously considers the influence of adjacent graphic dimensions and edge placement errors. Thus, the displacement of each contour edge segment in the hotspot layout can be iteratively optimized using this optimization objective function to obtain the displacement that satisfies the optimization objective function. This achieves automated correction of hotspot layouts without manual intervention, improving the efficiency of hotspot layout correction while effectively ensuring the accuracy and reliability of the correction results. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a flowchart illustrating the hotspot layout correction method in a mask layout provided in an embodiment of the present invention.

[0051] Figure 2 A schematic diagram of a first type of hotspot layout provided in an embodiment of the present invention;

[0052] Figure 3 A schematic diagram of a second type of hotspot layout provided in an embodiment of the present invention;

[0053] Figure 4 A schematic diagram of a third type of hotspot layout provided in an embodiment of the present invention;

[0054] Figure 5 A schematic diagram of the fourth type of hotspot layout provided in an embodiment of the present invention;

[0055] Figure 6 This is a structural block diagram of a hotspot layout correction device in a mask layout provided in an embodiment of the present invention. Detailed Implementation

[0056] The core of this invention is to provide a method, apparatus, device, and computer-readable storage medium for hotspot pattern correction in a mask pattern, which can improve the efficiency and accuracy of hotspot pattern correction without requiring excessive manual work.

[0057] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] like Figure 1 As shown, Figure 1 This is a flowchart illustrating the hotspot layout correction method in a mask layout provided in an embodiment of the present invention.

[0059] In one specific embodiment of the present invention, the hotspot layout correction method in the mask layout may include:

[0060] S1: Determine the hotspot layout in the initial mask layout.

[0061] It is understandable that the mask pattern of a photolithography mask is determined based on the target pattern to be exposed. However, due to optical proximity response, the exposure pattern of a mask pattern that is completely consistent with the target pattern is not consistent with the target pattern. Therefore, an initial mask pattern is first determined based on the target pattern, and then the optical proximity effect correction model (OPC model) is used to correct the optical proximity effect of the initial mask pattern in order to obtain a mask pattern that is consistent with the target pattern.

[0062] During the process of correcting the optical proximity effect in the initial mask layout, the pattern of the layout region forming hotspots within the initial mask layout generally cannot be corrected by the OPC model, thus resulting in an error. Therefore, this embodiment can obtain the uncorrectable error region by performing a global correction process based on the initial mask layout and the OPC model. The pattern structure of the error region is also used to determine the area where the hotspot layout is located in the initial mask layout.

[0063] Of course, this invention does not exclude the possibility of manually delineating hotspot areas in the initial mask layout to obtain a hotspot layout recognition model trained through a neural network. This recognition model is then used to automatically identify hotspot regions in the initial mask layout, and the graphic of these hotspot regions constitutes the hotspot layout. Other methods for identifying and determining hotspot layouts can also be sampled in this invention, which will not be listed here.

[0064] S2: Based on the graphic information of the hotspot map, determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map.

[0065] After selecting the hotspot pattern in the initial mask pattern, the environmental graphic parameters corresponding to each contour edge in the hotspot pattern can be further determined. It is understandable that in the conventional OPC correction process of the mask pattern, the contour edge lines of the initial mask pattern need to be divided into several contour edge segments (all straight lines). By offsetting each of these contour edge segments along a direction perpendicular to itself by a certain amount, the purpose of correcting the mask pattern is achieved. Similarly, in this embodiment, during the correction of the graphics in the hotspot pattern, the contour edge lines are also divided into several contour edge segments, and the process of optimizing and iterating the hotspot pattern is essentially the process of determining the displacement amount corresponding to each contour edge segment.

[0066] Based on the above discussion, this embodiment, considering the specific characteristics of hotspot patterns in the current mask layout, includes four different environmental graphic parameters for each contour edge segment: two-sided spacing difference, single-sided spacing contrast, linewidth uniformity, and two-sided density difference. These four different parameters characterize the properties of four different hotspot layouts. Of course, in practical applications, if it is clearly determined that the current hotspot layout only contains one or more of these hotspot layout structures, only one type of environmental graphic parameter can be calculated.

[0067] For a detailed explanation of the environmental graphics parameters, please refer to... Figures 2 to 5 , Figures 2 to 5 Four different typical hotspot maps are shown. It should be noted that... Figures 2 to 5 The dashed lines in the image represent the dividing lines of each contour edge segment in the hotspot map, with the thickened contour edge segment being the [number]th [section] in the entire hotspot map. Segment outline edge segment.

[0068] Based on this, Figure 2 This illustrates a hotspot map where the spacing between a particular graphic and its two adjacent graphics differs significantly. Figure 2 The hotspot pattern shown will produce strong asymmetric optical diffraction during exposure, which can easily cause bridging or necking problems. Figure 2 Taking the hotspot map as an example, for each contour edge segment in the hotspot map, the difference in spacing between it and the adjacent graphics on both sides can characterize whether there is an abnormal situation in the spacing between the adjacent graphics on both sides that causes the hotspot.

[0069] Based on the graphic information of the hotspot map and the first parameter formula This allows us to obtain the difference in the distance between the two sides corresponding to each contour edge segment; where, For the first The difference in spacing between the two sides of the segment outline edge segment. For the first The vertical distance between the segment outline edge segment and the left nearest figure and the right nearest figure, respectively.

[0070] Reference Figure 2 , for the For a segment's outline edge, the nearest edge outline graphics can be searched on both sides (outlines belonging to the same graphic should be excluded), where the first... The left side of the segment outline edge, the outline edge and the first The nearest neighboring figure with the smallest distance between the segment outline edges is the leftmost nearest figure. Similarly, in the 1st... The right side of the segment outline edge, the outline edge and the first The adjacent graphic with the smallest distance between the segment outline edges is the rightmost nearest graphic; it can be understood that in this embodiment, the left and right sides are relative to the first... Regarding the contour edge segment, in practical applications, for a single straight contour edge segment, if one side is selected as the left side, then the other side is the right side. This embodiment does not impose further restrictions on this. After determining the left nearest neighbor and right nearest neighbor graphics, the points perpendicular to the first... In the direction of the segment outline edge segment, the first The distance between the edge segment of the segment and its left and right nearest neighbor figures is _____. and Of course, after determining and During the process, the first should be excluded The spacing dimension occupied by the graphic to which the segment outline edge segment belongs.

[0071] Reference Figure 3 , Figure 3 This shows a hotspot map where the spacing between different sections on one side of a graphic and between adjacent graphics varies significantly. Figure 3 The hotspot patterns shown tend to appear in patterns with a mix of long and short lines. Typically, the spacing between the edges of a certain graphic varies significantly, with dense lines having smaller spacing and stronger light intensity, while sparse lines have larger spacing and weaker light intensity, forming "sea outlet" type hotspots. To quantify the hotspots caused by this variation in spacing, the concept of spacing contrast is introduced. The process of determining the spacing contrast in the environmental graphic parameters of the contour edge segment can include:

[0072] Based on the graphic information of the hotspot map and the second parameter formula To obtain the single-sided spacing contrast corresponding to each contour edge segment; wherein, For the first The contrast of the spacing between the two sides of the segment outline edge segment. For the first The vertical distance between the edge of the segment outline and its nearest neighboring graphic.

[0073] like Figure 3 As shown, in Figure 3 In the hotspot map shown, the first The two adjacent contour edge segments are the first segment. The outline edge segment, and They are the first The three contour edge segments are respectively located at the vertical distances between themselves and their nearest neighboring figures on the same side, where "same side" refers to the first... The three contour edge segments are on the outside of the same graphic structure to which they belong; for example, in Figure 3 In the graphical structure shown, when the first If all three contour edge segments are located on the right side of the same graphic, then the nearest graphics to each of the three contour edge segments on the right side can be searched, and the distance between each contour edge segment and its corresponding nearest graphics in the direction perpendicular to the contour edge segment itself can be determined. In short, when determining the unilateral spacing contrast, the vertical distance between each contour edge segment and its nearest graphics on the side opposite to the graphic it is located is determined. When the unilateral spacing contrast determined based on the above second parameter formula is large, a significant unilateral spacing change appears near the contour edge segment, which is prone to necking problems.

[0074] like Figure 4 As shown, Figure 4 This illustrates a hotspot pattern where the graphic itself exhibits uneven linewidth. This results in patterns with significant width variations, such as dumbbell-shaped or large-corner shapes, appearing within the hotspot pattern. Uneven light intensity distribution at these size variations further exacerbates hotspot issues, including edge placement errors, bridging, or necking. Therefore, to quantify this type of hotspot pattern, environmental graphic parameters characterizing the degree of linewidth unevenness are introduced. Optionally, the process of determining linewidth uniformity can be as follows:

[0075] Based on the graphic information of the hotspot map and the third parameter formula This yields the linewidth uniformity corresponding to each contour edge segment; where, For the first Uniformity of line width of segment outline edge segments For the first The line width value between the edge segment of the profile and the edge segment of the opposite profile.

[0076] like Figure 4 As shown, in determining the first When determining the line width of a segment's outline edge, a perpendicular line drawn from the midpoint of that segment can be drawn. The distance between the edge line on the graphic containing the segment and the perpendicular line intersecting this line, and the segment itself, along the perpendicular line, is the line width value corresponding to that segment. Similarly, the line width of the first segment can be determined. The line width values ​​corresponding to the contour edge segment and its two adjacent contour edge segments can be substituted into the formula for the third parameter to determine the first line width. The uniformity of linewidth corresponding to the contour edge segments. Obviously, in this embodiment, the linewidth uniformity mainly characterizes the degree of significant change in the linewidth value corresponding to the contour edge segment and the linewidth value corresponding to adjacent contour edge segments.

[0077] Reference Figure 5 , Figure 5 This illustrates a hotspot map where the density distribution on both sides of the graphic differs significantly. For example... Figure 5 In the hotspot map shown, if the density of adjacent patterns on both sides of one pattern differs significantly, the side with the higher density will have higher light intensity during actual exposure, easily causing exposure position shift. To quantify such hotspot environments, the density difference between the two sides is introduced as an environmental pattern parameter. Optionally, the process of determining the density difference between the two sides can be as follows:

[0078] Based on the graphic information of the hotspot map and the fourth parameter formula The density difference between the two sides of each contour edge segment is obtained; where, For the first Density difference between the two sides of the segment outline edge segment To respectively along the first The left and right nearest neighbor graphic densities are set within the area range along the normal direction on both sides of the segment outline edge. To set non-zero positive numbers.

[0079] Reference Figure 5 In determining the density of the left nearest neighbor graphic and the density of the right nearest neighbor graphic for each contour edge segment, a left search area and a right search area should be defined on the left and right sides of the contour edge segment according to the set search distance range. The proportion of the area of ​​the neighboring graphic in the left search area to the area of ​​the left search area is the density of the left nearest neighbor graphic, and the proportion of the area of ​​the neighboring graphic in the right search area to the area of ​​the right search area.

[0080] In this embodiment, the set search distance can be 3 times the minimum period of the initial mask layout (the minimum repetition spacing of periodic graphic units in the mask layout in a specified direction, which is a known core parameter); and the two search regions should be regions with the same shape and area, specifically rectangular regions.

[0081] For the The two search regions corresponding to the segment outline edge segment, the first search region is in the first... The edge of the segment's outline is away from one side of the graphic it belongs to, with the first... The edge segment of the profile is the center of one side of the side, along the perpendicular to the first... The dimension of the segment outline edge along the segment direction is equal to a rectangular area defined by the set search distance; and the first search area is related to the second... The initial delineation area is symmetrical along the edge segment of the contour, perpendicular to the first... The segment outline edge is translated upwards towards the side away from the first search area. The area enclosed by the distance is the second search area.

[0082] like Figure 5 The first in Taking the right-side search area of ​​the segment outline edge as an example, this right-side search area can be a region with side lengths of and respectively. The rectangular region whose outline edge segments are parallel and perpendicular, and whose left side is defined by the first segment. Centered on the edge segment of the outline, with a length three times the length of the outline edge segment, along the perpendicular to the first... The dimension of the side length in the direction of the segment outline is equal to the set search distance.

[0083] Similarly, for the first The search area to the left of the segment outline edge should also be the area with side lengths of and respectively. The rectangular region with parallel and perpendicular edges of the segment outline can be initially defined by taking the right edge as the first... Centered on the edge segment of the outline, with a length three times the length of the outline edge segment, along the perpendicular to the first... The side length of the segment outline edge in the direction of the segment is equal to the set search distance to define a rectangular area, and then the rectangular area is translated to the left. The line width value is used to exclude the first... The area occupied by the edge segment of the segment outline within the left search area can be used to obtain the left search area.

[0084] Of course, all of the above are based on the first Taking the example of rectangular areas on both sides of the contour edge segment as an illustration, in practical applications, this invention does not exclude the possibility that each search area is circular or other polygonal. The shape of the specific search area can be determined based on the direction of the contour line where the contour edge segment is located, and the direction of the edge line on the opposite side of the contour edge segment on the same graphic. It should be ensured that at least one side of the search area is parallel to the edge line where the contour edge segment is located or parallel to the edge line on the opposite side of the contour edge segment, and the size in the direction perpendicular to the contour edge segment is equal to the set search distance.

[0085] After determining the search areas on both sides of the contour edge segment, the graphic density of each search area can be determined based on the ratio of the area occupied by the graphic structure within that search area to the total area of ​​that search area. Based on this, and using the aforementioned fourth parameter formula, It can be a very small non-zero positive number, which can prevent the denominator from being 0 when both sides of the graph are isolated, thus preventing the formula from being calculated.

[0086] Based on the above four parameter formulas, after obtaining the hotspot map, the calculation of the four environmental graphic parameters corresponding to each contour edge segment in the hotspot map can be performed. It should also be noted that the calculations in the above second and third parameter formulas both involve... In the parameter calculation of three consecutive adjacent contour edge segments, "consecutive adjacent" in this embodiment refers to being adjacent in terms of graphic structure, not just in terms of the sequence number of the contour edge segments. For example, in a hotspot map containing three graphic structures, the sequence numbers of the contour edge segments in the first graphic structure are 1 to k, while the sequence numbers of the contour edge segments in the second graphic structure are k+1 to 3k. Therefore, for the kth contour edge segment, its adjacent contour edge segments should be the 1st contour edge segment and the (k-1)th contour edge segment, not the (k-1)th contour edge segment and the (k+1)th contour edge segment.

[0087] Furthermore, in order to minimize the complexity of calculating the environmental graphic parameters corresponding to the contour edge segments in the hotspot map, in another optional embodiment of the present invention, the process of determining the environmental graphic parameters of the contour edge segments in the hotspot map may further include:

[0088] S21: Perform similarity calculation between the hotspot map and the pre-stored sample hotspot map to obtain the maximum similarity among all similarities;

[0089] S22: Determine whether the maximum similarity is greater than the set similarity threshold. If yes, proceed to S23; otherwise, proceed to S24.

[0090] S23: Use the sample environment graphic parameters of the hotspot map corresponding to the maximum similarity as the environment graphic parameters corresponding to each contour edge segment of the hotspot map.

[0091] S24: Calculate the environmental graphic parameters of each contour edge segment based on the graphic information of the hotspot map, and store the hotspot map and the corresponding environmental graphic parameters as new sample hotspot map and corresponding sample environmental graphic parameters in the database; wherein, the environmental graphic parameters include at least one of the following parameters: the difference between the two sides spacing, the contrast between the two sides spacing, the uniformity of the line width, and the difference between the two sides density.

[0092] In this embodiment, a database of hotspot maps is pre-created. This database stores different sample hotspot maps and their sample environmental graphic parameters. In other words, it is equivalent to creating a database containing the relationship between hotspot maps and their corresponding sample environmental graphic parameters. Therefore, when determining the environmental graphic parameters corresponding to a hotspot map, a sample hotspot map with a high similarity to the current hotspot map can be searched in the database. The sample environmental graphic parameters corresponding to the sample hotspot map can then be used as the environmental graphic parameters of the current hotspot map.

[0093] In the process of searching for sample hotspot maps with high similarity to hotspot maps in the database, any algorithm such as Scale-Invariant Feature Transform (SIFT), SpeededUp Robust Feature (sSURF), or Oriented Fast and Rotated BRIEF can be used to perform feature matching operations to determine sample hotspot maps with a similarity of more than 95% to the graphic characteristics of the hotspot map, that is, matching the hotspot map.

[0094] Of course, if there is no sample hotspot map in the database that matches the current hotspot map, it means that the current hotspot map is a new hotspot map. The environmental graphic parameters of the current hotspot map can be directly calculated according to the first parameter formula, the second parameter formula, the third parameter formula and the fourth parameter formula mentioned above. This will optimize the displacement of the subsequent contour edge segment. At the same time, the hotspot map and the corresponding environmental graphic parameters can be stored in the database as new sample hotspot map and sample environmental graphic parameters, respectively, to expand and update the samples in the database.

[0095] S3: Based on the edge placement error that varies with the displacement of the contour edge segment, construct a basic optimization objective function with the displacement of the contour edge segment as the variable.

[0096] In this embodiment, a basic optimization objective function is constructed based on the edge placement error (i.e., the deviation between the imaging position and the target position) that varies with the displacement of the contour edge segment. This ensures that the final optimization direction is to iterate in the direction of reducing the edge placement error corresponding to the contour edge segment, thus guaranteeing the accuracy and reliability of the optimization results.

[0097] Optionally, the basic optimization objective function constructed in this embodiment may include:

[0098] ;in, and The first The deviation function between the imaging position and the target position of the segment contour edge segment under nominal process conditions and preset worst process conditions; For the first The displacement corresponding to the edge segment of the segment contour. This represents the total number of all outline edge segments in the hotspot map; All are proportional parameters, satisfying ,and .

[0099] It should be noted that, Under nominal process conditions (optimal focal length and optimal exposure dose), the first The edge placement error of a segment's contour edge is a quadratic function of the segment's displacement. This refers to the edge placement error under the worst-case process conditions (such as focal length shift or exposure dose fluctuation). The stability of the displacement scheme under process fluctuation conditions was measured.

[0100] In the OPC model, a first-order linear model is typically used to approximate the relationship between edge placement error and displacement. This allows us to determine the relationship for the first... Segment outline edge segment, It can be represented as: ;in, Under nominal process conditions, the first When the displacement of the segment outline edge segment is 0, the first... The edge placement error corresponding to the segment outline edge; Under nominal process conditions For the The displacement sensitivity coefficient of the edge segment of the contour (also known as an element of the optical proximity effect matrix), that is, the first... The segment outline edge segment moves 1 unit distance to the first segment. Segment edge segment The resulting impact.

[0101] akin, This can be expressed as ;in, To achieve the best-case scenario under the preset process conditions, the first When the displacement of the segment outline edge segment is 0, the first... The edge placement error corresponding to the segment outline edge; Under the worst-case scenario conditions For the The displacement sensitivity coefficient of the edge segment of the contour (also known as an element of the optical proximity effect matrix), that is, the first... The segment outline edge moves 1 unit distance to the edge of The resulting impact.

[0102] The last term in the above basic optimization objective function It is a perturbation penalty term controlling the displacement function, in the form of the sum of squared displacements, to avoid new violations caused by drastic local displacements, and to prevent the objective function from being over-corrected during the optimization iteration process. Furthermore, It is the scaling factor of each term, controlling the proportion of each term in the optimization objective function, and satisfying the following: Typically, during the optimization and iterative correction of displacement, it is necessary to ensure the nominal environment (nominal process conditions). Convergence, therefore requires Maximum, such as ,and Representing non-nominal conditions The weight of has a small proportion in the final correction, so it can be set The proportion of the disturbance term should be adjusted according to the actual situation, and the proportion should not be too large to avoid limiting the displacement to a small range, which would lead to inadequate correction. Therefore, a suitable proportion can be taken as follows: .

[0103] S4: Determine the optimization compensation terms based on the environmental graphical parameters, and superimpose the optimization compensation terms and the basic optimization objective function to obtain the optimization objective function.

[0104] Based on the above discussion, after creating the basic optimization objective function, further optimization compensation terms can be added to the basic optimization objective function according to the environmental graphic parameters corresponding to each contour edge segment in the hotspot map.

[0105] In an optional embodiment of the present invention, the process of adding an optimization compensation term to the basic optimization objective function based on the environmental graphical parameters of the hotspot map to obtain the final optimization objective function may include:

[0106] S41: Based on the environmental graphic parameters and the set anomaly threshold, determine the first set of contour edge segments composed of contour edge segments with abnormal spacing difference on both sides, the second set of contour edge segments composed of contour edge segments with abnormal spacing contrast on one side, the third set of contour edge segments composed of contour edge segments with abnormal line width uniformity, and the fourth set of contour edge segments composed of contour edge segments with abnormal density difference on both sides.

[0107] S42: Based on the first contour edge segment set and spacing balance term formula Determine the spacing balance term; among which, For spacing balance, As the first weight parameter, This represents the total number of contour edge segments on the near-spacing side in the first contour edge segment set. The sequence number of each contour edge segment on the near-spacing side in the first contour edge segment set; This represents the total number of contour edge segments on the far-spaced side in the first contour edge segment set. This refers to the sequence number of the contour edge segment on the far side in the first contour edge segment set. To set the magnification factor;

[0108] S43: Based on the set of the second contour edge segments and the formula for the cooperative variation term Determine the cooperative variation terms; among which, For cooperative change terms, This is the second weighting parameter. This represents the total number of contour edge segments in the second contour edge segment set. This refers to the sequence number of the contour edge segment in the second contour edge segment set;

[0109] S44: Based on the third contour edge segment set and width protection formula Determine the width protection item; among which, For width protection items, As the third weighting parameter, This represents the total number of contour edge segments in the third contour edge segment set. This refers to the index of the contour edge segment in the third contour edge segment set. To adjust the parameters and satisfy , ;

[0110] S45: Based on the formula for the fourth contour edge segment set and density balance term Determine the density equilibrium term; among which, For density equilibrium, This is the fourth weighting parameter. This represents the total number of low-density side contour edge segments in the fourth contour edge segment set. The sequence number of the low-density side contour edge segment in the fourth contour edge segment set; This represents the total number of high-density side contour edge segments in the fourth contour edge segment set. The sequence number of the high-density side contour edge segment in the fourth contour edge segment set;

[0111] S46: Based on the basic optimization objective function, and using at least one of the following compensation terms—spacing balance term, cooperative variation term, width protection term, and density balance term—to construct the optimization objective function as follows: ;in, To optimize the calculated value of the objective function, The basic optimization objective function is defined as follows.

[0112] In this embodiment, a corresponding abnormal threshold is set for each environmental graphic parameter. For example, when the first parameter is... The difference in spacing between the two sides of the segment outline edge segment satisfies When the distance between the two sides of the contour edge segment is considered to be significantly abnormal; when the first The difference in spacing between the two sides of the segment outline edge segment satisfies When the distance is large, it is considered that there is a large difference in spacing on one side of the contour edge segment; when the first... The difference in spacing between the two sides of the segment outline edge segment satisfies When the line width uniformity of the contour edge segment is abnormal, it is considered that there is an anomaly in the uniformity of the line width; when the first The difference in spacing between the two sides of the segment outline edge segment satisfies If the density of the graphics on both sides of the contour edge segment is significantly unbalanced, there is an abnormal difference in the distance between the two sides.

[0113] It is understandable that the set anomaly thresholds for different exposure process conditions and different mask patterns are different. Therefore, in practical applications, the appropriate range of anomaly parameters can be determined based on human experience or by conducting targeted tests.

[0114] Based on different preset anomaly thresholds, the presence of anomalies in each contour edge segment can be determined by the four environmental graphic parameters corresponding to each contour edge segment. If there is a difference in the spacing between the two sides of the contour edge segment, then the contour edge segment belongs to the first contour edge segment set. If there is an anomaly in the spacing contrast on one side, then it belongs to the second contour edge segment set. If there is an anomaly in the line width uniformity, then it belongs to the third contour edge segment set. If there is an anomaly in the density difference between the two sides, then it belongs to the fourth contour edge segment set.

[0115] Based on this, if the set of first contour edge segments corresponding to the hot spot map is not an empty set, the spacing balance term can be determined according to the first contour edge segment set and the spacing balance term formula, and the spacing balance term can be used as an optimization compensation term.

[0116] It should be noted that the contour edge segments with abnormal differences in the distance between the two sides included in the first set of contour edge segments further include contour edge segments on the near-distance side and contour edge segments on the far-distance side. For example... Figure 2 As shown, when the first The edge of the segment's outline is located to the right of the figure it belongs to, and the vertical distance between the leftmost neighboring figure and the rightmost neighboring figure is greater than the vertical distance between them. Then the first The contour edge segment is the contour edge segment on the side closest to the spacing; conversely, when the first segment... The edge of the segment's outline is located to the right of the figure it belongs to, and the vertical distance between the leftmost neighboring figure and the rightmost neighboring figure is less than the vertical distance between them. Then the first The contour edge segment is the contour edge segment on the far-spacing side. In summary, if the side of the contour edge segment on the graphic has a smaller vertical distance from the side of its nearest neighboring graphic, then the contour edge segment is on the near-spacing side; otherwise, it is on the far-spacing side. In the above spacing balance formula, To set the amplification factor, which represents the proportion of the displacement borne by the far-space side to the adjustment amount of the near-space side; This refers to the weighting parameter of the optimization compensation term. In this embodiment, the spacing balance term guides the contour edge segment on the far-spacing side to bear more displacement, giving the contour edge segment on the near-spacing side more correction space, thereby improving the correction accuracy of contour edge segments with abnormal spacing differences between the two sides.

[0117] If the set of second contour edge segments corresponding to the hotspot map is not empty, then the collaborative change term can be determined based on the set of second contour edge segments and the collaborative change term formula, and used as an optimization compensation term. In this embodiment, the collaborative change term can guide the uniform and continuous change of displacement between multiple contour edge segments on one side, preventing the phenomenon of excessive displacement of a single contour edge segment, which would make it difficult to converge the local edge placement error.

[0118] If the set of third contour edge segments corresponding to the hotspot map is not empty, then the width protection term can be determined based on the set of third contour edge segments and the width protection term formula, and used as an optimization compensation term. In the width protection term formula... To adjust the parameters, All are set positive numbers. For example, when the displacement is less than 0, that is, when the contour edge segment moves inward into the graphic, When the displacement is greater than 0, that is, when the contour edge segment moves outwards from the graphic, This implements a penalty for inward movement while allowing outward movement. Therefore, this width protection feature can protect narrower areas from outward movement while hindering inward movement, preventing necking in narrow areas and thus ensuring correction accuracy.

[0119] If the set of fourth contour edge segments corresponding to the hotspot map is not empty, the density balance term can be determined as an optimization compensation term based on the set of fourth contour edge segments and the density balance term formula. The fourth contour edge segment set includes contour edge segments with density differences on both sides, including contour edge segments on the high-density side and contour edge segments on the low-density side. When the side of a contour edge segment on the graphic is the same as the side with the higher graphic density, then the contour edge segment is a contour edge segment on the high-density side; otherwise, it is a contour edge segment on the low-density side. For example... Figure 5As shown, when the contour edge segment is located on the right side of the graphic it belongs to, and the graphic density in the search area on its right is greater than the graphic density in the search area on its left, then the contour edge segment is the contour edge segment on the high-density side.

[0120] In the density equilibrium term, The parameter used to guide the displacement of the contour edge segments toward the high-density side can be a small value, such as 0.001 micrometers; the density equalization term guides the overall pattern to produce a slight shift toward the low-density side to compensate for the exposure dose differences of the contour edge segments.

[0121] Based on the above discussion, on the basis of constructing and determining the basic optimization objective function, for each type of anomaly edge segment in the hotspot map, a corresponding optimization compensation term is added for correction, which ensures the accuracy and reliability of the correction results while ensuring rapid optimization in the optimization iteration process.

[0122] It is understandable that if any one of the above four contour edge segment sets (first, second, third, and fourth) is empty, then the corresponding optimization compensation term does not need to be added to the optimization objective function. If none of the above four contour edge segment sets are empty, then the optimization objective function can be expressed as:

[0123] .

[0124] S5: Optimize the displacement of each contour edge segment according to the optimization objective function, and obtain the corrected displacement corresponding to each contour edge segment so that the calculated value of the optimization objective function reaches the optimization objective, so as to determine the corrected layout of the hot spot layout.

[0125] After determining the objective function, the displacements and variables corresponding to all contour edge segments are optimized simultaneously. This allows the contour edge segments to influence each other through mutual constraints and guidance, ultimately obtaining the corrected displacement corresponding to the contour edge segment when the calculated value of the objective function is minimized. Based on this corrected displacement, the corrected hotspot map can be obtained.

[0126] Further, optionally, the process of optimizing the displacement of each contour edge segment based on the objective function may also include:

[0127] With the constraints that the displacement is within a set displacement range, and the spacing parameter corresponding to each contour edge segment is not less than the minimum spacing, and the corresponding line width parameter is not less than the minimum line width, the displacement of each contour edge segment is optimized iteratively to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective.

[0128] In this embodiment, the minimum spacing and minimum linewidth are the minimum allowable spacing parameter between adjacent patterns in the mask layout and the linewidth parameter corresponding to each pattern, respectively. By setting reasonable constraints, this embodiment can ensure the reliability of the optimization iteration results to a certain extent.

[0129] Based on the above discussion, in order to further ensure the accuracy and reliability of the revised map corresponding to the final hotspot map, the following can be further included:

[0130] Exposure simulation is performed on the corrected pattern to obtain the simulated exposure pattern;

[0131] The consistency between the simulated exposure pattern and the hotspot pattern is verified. If the verification fails, the weighting coefficients of each item in the optimization objective function corresponding to each contour edge segment are adjusted, and the correction displacement corresponding to each contour edge segment is re-determined based on the updated optimization objective function to obtain the corrected pattern of the hotspot pattern update.

[0132] In this embodiment, adjusting the weight coefficients of each item may refer to adjusting the weight coefficients in the basic objective function. as well as Adjustments are made to multiple coefficients.

[0133] In summary, this invention is based on the principle that hotspots in a mask layout arise from the unique relative dimensions between certain graphic contours and adjacent graphics. During the correction of hotspot layouts in the mask layout, environmental graphic parameters characterizing the relative dimensions between each contour edge segment and adjacent graphics are determined. A basic optimization objective function is constructed based on the edge placement error varying with displacement. Furthermore, optimization compensation terms are added to the baseline optimization objective function based on the environmental graphic parameters corresponding to each contour edge segment. This ensures that the final optimization objective function simultaneously considers the influence of adjacent graphic dimensions and edge placement errors. Thus, this optimization objective function can be used to iteratively optimize the displacement of each contour edge segment in the hotspot layout, ultimately obtaining the displacement that satisfies the optimization objective function. This achieves automated correction of hotspot layouts without manual intervention, improving the efficiency of hotspot layout correction while effectively ensuring the accuracy and reliability of the correction results.

[0134] The following describes the hotspot pattern correction device in the mask layout provided by the embodiments of the present invention. The hotspot pattern correction device in the mask layout described below can be referred to in correspondence with the hotspot pattern correction method in the mask layout described above.

[0135] Figure 6 This is a structural block diagram of a hotspot layout correction device in a mask layout provided in an embodiment of the present invention, with reference to... Figure 6 The hotspot layout correction device in the mask layout may include:

[0136] Hotspot determination module 100 is used to determine the hotspot layout in the initial mask layout;

[0137] The parameter calculation module 200 is used to determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map based on the graphic information of the hotspot map.

[0138] The function construction module 300 is used to construct a basic optimization objective function with the displacement of the contour edge segment as the variable, based on the edge placement error that varies with the displacement of the contour edge segment under nominal and non-nominal exposure processes.

[0139] The function adjustment module 400 is used to determine the optimization compensation item based on the abnormal parameters in each of the environmental graphic parameters, and to superimpose the optimization compensation item and the basic optimization objective function to obtain the optimization objective function.

[0140] The optimization calculation module 500 is used to optimize the displacement of each contour edge segment according to the optimization objective function, and obtain the corrected displacement corresponding to each contour edge segment so that the calculated value of the optimization objective function reaches the optimization objective, so as to determine the corrected layout of the hotspot layout.

[0141] In an optional embodiment of the present invention, the parameter calculation module 200 is specifically used to perform similarity calculation on the hotspot map and the pre-stored sample hotspot map to obtain the maximum similarity among the similarities; determine whether the maximum similarity is greater than a set similarity threshold; if so, use the sample environment graphic parameters of the sample hotspot map corresponding to the maximum similarity as the environment graphic parameters corresponding to each contour edge segment of the hotspot map; if not, calculate the environment graphic parameters of each contour edge segment according to the graphic information of the hotspot map, and store the hotspot map and the corresponding environment graphic parameters as new sample hotspot map and corresponding sample environment graphic parameters in the database; wherein, the environment graphic parameters include at least one of the following parameters: side spacing difference, single-side spacing contrast, line width uniformity, and side density difference.

[0142] In an optional embodiment of the present invention, the parameter calculation module 200 specifically includes:

[0143] The first calculation unit is used to calculate the hotspot map's graphic information and the first parameter formula. The difference in the distance between the two sides corresponding to each contour edge segment is obtained; wherein, For the first The difference in spacing between the two sides of the segment outline edge segment. For the first The vertical distances between the edge segment of the outline and its left and right nearest neighbor figures, respectively;

[0144] The second calculation unit is used to calculate the hotspot map based on the graphic information and the second parameter formula. The single-sided spacing contrast corresponding to each contour edge segment is obtained; wherein, For the first The contrast of the spacing between the two sides of the segment outline edge segment. For the first The vertical distance between the edge segment of the segment outline and its nearest neighboring shape;

[0145] The third calculation unit is used to calculate the hotspot map's graphic information and the third parameter formula. To obtain the linewidth uniformity corresponding to each of the contour edge segments; wherein, For the first Uniformity of line width of segment outline edge segments For the first The line width value between the edge segment of the profile segment and the edge segment of the opposite profile segment;

[0146] The fourth calculation unit is used to calculate the hotspot map's graphic information and the fourth parameter formula. The density difference between the two sides corresponding to each contour edge segment is obtained; wherein, For the first Density difference between the two sides of the segment outline edge segment To respectively along the first The left and right nearest neighbor graphic densities are set within the area range along the normal direction on both sides of the segment outline edge. To set non-zero positive numbers.

[0147] In an optional embodiment of the present invention, the function construction module 300 is used to construct the basic optimization objective function as follows: ;in, and The first The deviation function between the imaging position and the target position of the segment contour edge segment under nominal process conditions and preset worst process conditions; For the first The displacement corresponding to the edge segment of the segment contour. This represents the total number of all outline edge segments in the hotspot map; All are proportional parameters, satisfying ,and .

[0148] In an optional embodiment of the present invention, the function adjustment module 400 includes:

[0149] An anomaly calculation unit is used to determine, based on the environmental graphic parameters and a set anomaly threshold, a first set of contour edge segments composed of contour edge segments with abnormal spacing difference on both sides, a second set of contour edge segments composed of contour edge segments with abnormal spacing contrast on one side, a third set of contour edge segments composed of contour edge segments with abnormal line width uniformity, and a fourth set of contour edge segments composed of contour edge segments with abnormal density difference on both sides.

[0150] The first compensation term unit is used to calculate the first contour edge segment set and the spacing balance term formula. Determine the spacing balance term; among which, For the spacing balance term, As the first weight parameter, This represents the total number of contour edge segments on the near-spacing side in the first set of contour edge segments. The sequence number of each contour edge segment on the near-spacing side in the first contour edge segment set; This represents the total number of contour edge segments on the far-spaced side in the first set of contour edge segments. The sequence number of the contour edge segment on the far side in the first set of contour edge segments; To set the magnification factor;

[0151] The second compensation term unit is used to calculate the second contour edge segment set and the cooperative change term formula. Determine the cooperative variation terms; among which, For the aforementioned collaborative change term, This is the second weighting parameter. This represents the total number of contour edge segments in the second set of contour edge segments. This refers to the sequence number of the contour edge segment in the second contour edge segment set;

[0152] The third compensation term unit is used to calculate the third contour edge segment set and the width protection term formula. Define the width protection item; among which, For the width protection item, As the third weighting parameter, The total number of contour edge segments in the third contour edge segment set. The sequence number of the contour edge segment in the third contour edge segment set. To adjust parameters and satisfy , ;

[0153] The fourth compensation term unit is used to calculate the fourth contour edge segment set and density equalization term formula. Determine the density equilibrium term; among which, For the density balance term, This is the fourth weighting parameter. The total number of low-density side contour edge segments in the fourth contour edge segment set. The sequence number of the low-density side contour edge segment in the fourth contour edge segment set; The total number of high-density side contour edge segments in the fourth contour edge segment set. The sequence number of the high-density side contour edge segment in the fourth contour edge segment set; These are constant parameters;

[0154] An adjustment unit is constructed to construct an optimization objective function based on the basic optimization objective function, using the spacing balance term, the cooperative change term, the width protection term, and the density balance term as optimization compensation terms. ;in, To optimize the calculated value of the objective function, Let be the basic optimization objective function.

[0155] In an optional embodiment of the present invention, the optimization calculation module 500 is specifically used to optimize and iterate the displacement of each contour edge segment under the constraint that the displacement is within a set displacement range and the spacing parameter corresponding to each contour edge segment is not less than the minimum spacing and the corresponding line width parameter is not less than the minimum line width, so as to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective.

[0156] In an optional embodiment of the present invention, a simulation verification module is further included, which is used to perform exposure simulation on the corrected layout to obtain a simulated exposure graphic; to verify the consistency between the simulated exposure graphic and the hotspot layout; if the verification fails, the weighting coefficients of each item of the optimization objective function corresponding to each contour edge segment are adjusted, and the corrected displacement corresponding to each contour edge segment is re-determined according to the updated optimization objective function to obtain the corrected layout updated by the hotspot layout.

[0157] The hotspot pattern correction device in the mask pattern of this embodiment is used to implement the aforementioned hotspot pattern correction method in the mask pattern. Therefore, the specific implementation of the hotspot pattern correction device in the mask pattern can be found in the embodiment section of the hotspot pattern correction method in the mask pattern above. The specific implementation can be referred to the description of the corresponding embodiments, and will not be repeated here.

[0158] The present invention also provides an embodiment of a hotspot pattern correction device in a mask layout, the hotspot pattern correction device in the mask layout may include:

[0159] Memory, used to store computer programs;

[0160] A processor for executing a computer program to implement the steps of the hotspot layout correction method in a mask layout as described in any of the preceding claims.

[0161] The steps of the hotspot layout correction method in the mask layout executed by the processor may include:

[0162] A hotspot pattern is determined in the initial mask pattern. Based on the graphic information of the hotspot pattern, environmental graphic parameters corresponding to each contour edge segment in the hotspot pattern are determined. Based on the edge placement error that varies with the displacement of the contour edge segment under nominal and non-nominal exposure processes, a basic optimization objective function is constructed with the displacement of the contour edge segment as the variable. An optimization compensation term is determined based on the abnormal parameters in each of the environmental graphic parameters. The optimization compensation term and the basic optimization objective function are superimposed to obtain an optimization objective function. The displacement of each contour edge segment is optimized according to the optimization objective function to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization target, thereby determining the corrected pattern of the hotspot pattern.

[0163] The present invention also provides a computer-readable storage medium storing a computer program that is executed to implement the steps of the hotspot layout correction method in the mask layout as described in any of the preceding claims.

[0164] The computer-readable storage medium may include random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0165] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that the elements inherent in a process, method, article, or apparatus that includes a list of elements are included. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Additionally, portions of the technical solutions provided in the embodiments of the present invention that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0166] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A method for correcting hotspot patterns in a mask layout, characterized in that, include: Determine the hotspot layout in the initial mask layout; Based on the graphic information of the hotspot map, determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map; Based on the edge placement error that varies with the displacement of the contour edge segment, a basic optimization objective function is constructed with the displacement of the contour edge segment as the variable. Based on the environmental graphical parameters, the optimization compensation terms are determined, and the optimization compensation terms are superimposed with the basic optimization objective function to obtain the optimization objective function. The displacement of each contour edge segment is optimized according to the optimization objective function to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective, so as to determine the corrected layout of the hotspot layout.

2. The hotspot layout correction method in a mask layout as described in claim 1, characterized in that, Based on the graphic information of the hotspot map, determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map, including: The similarity between the hotspot map and the pre-stored sample hotspot map is calculated to obtain the maximum similarity among all similarity values. Determine whether the maximum similarity is greater than a set similarity threshold; If so, the sample environment graphic parameters of the sample hotspot map corresponding to the maximum similarity are used as the environment graphic parameters corresponding to each contour edge segment of the hotspot map. If not, then the environmental graphic parameters of each contour edge segment are calculated based on the graphic information of the hotspot map, and the hotspot map and the corresponding environmental graphic parameters are stored in the database as new sample hotspot maps and corresponding sample environmental graphic parameters; wherein, the environmental graphic parameters include at least one of the following parameters: side spacing difference, single-side spacing contrast, line width uniformity, and side density difference.

3. The hotspot layout correction method in a mask layout as described in claim 1, characterized in that, Based on the graphic information of the hotspot map, determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map, including: Based on the graphic information of the hotspot map and the first parameter formula The difference in the distance between the two sides corresponding to each contour edge segment is obtained; wherein, For the first The difference in spacing between the two sides of the segment outline edge segment. For the first The vertical distances between the edge segment of the outline and its left and right nearest neighbor figures, respectively; Based on the graphic information of the hotspot map and the second parameter formula The single-sided spacing contrast corresponding to each contour edge segment is obtained; wherein, For the first The contrast of the spacing between the two sides of the segment outline edge segment. For the first The vertical distance between the edge segment of the segment outline and its nearest neighboring shape; Based on the graphic information of the hotspot map and the third parameter formula To obtain the linewidth uniformity corresponding to each of the contour edge segments; wherein, For the first Uniformity of line width of segment outline edge segments For the first The line width value between the edge segment of the profile segment and the edge segment of the opposite profile segment; Based on the graphic information of the hotspot map and the fourth parameter formula The density difference between the two sides corresponding to each contour edge segment is obtained; wherein, For the first Density difference between the two sides of the segment outline edge segment To respectively along the first Set the left nearest neighbor and right nearest neighbor graphic densities within the search distance along the normal direction on both sides of the segment outline edge. To set non-zero positive numbers.

4. The hotspot layout correction method in a mask layout as described in claim 1, characterized in that, Based on the edge placement error that varies with the displacement of the contour edge segment, a basic optimization objective function is constructed with the displacement of the contour edge segment as the variable, including: The basic optimization objective function is constructed as follows: ;in, and The first The deviation function between the imaging position and the target position of the segment contour edge segment under nominal process conditions and preset worst process conditions; For the first The displacement corresponding to the edge segment of the segment contour. This represents the total number of all contour edge segments in the hotspot map; All are proportional parameters, satisfying ,and .

5. The hotspot layout correction method in a mask layout as described in any one of claims 1 to 4, characterized in that, Based on the environmental graphical parameters, optimization compensation terms are determined. These optimization compensation terms are then superimposed with the basic optimization objective function to obtain the optimization objective function, which includes: Based on the environmental graphic parameters and the set anomaly threshold, a first set of contour edge segments consisting of contour edge segments with abnormal spacing difference on both sides, a second set of contour edge segments consisting of contour edge segments with abnormal spacing contrast on one side, a third set of contour edge segments consisting of contour edge segments with abnormal line width uniformity, and a fourth set of contour edge segments consisting of contour edge segments with abnormal density difference on both sides are determined. Based on the first set of contour edge segments and the spacing balance formula Determine the spacing balance term; among which, For the spacing balance term, As the first weight parameter, This represents the total number of contour edge segments on the near-spacing side in the first set of contour edge segments. The sequence number of each contour edge segment on the near-spacing side in the first contour edge segment set; This represents the total number of contour edge segments on the far-spaced side in the first set of contour edge segments. The sequence number of the contour edge segment on the far side in the first set of contour edge segments; To set the magnification factor; Based on the second contour edge segment set and the formula for cooperative variation term Determine the cooperative variation terms; among which, For the aforementioned collaborative change term, This is the second weighting parameter. This represents the total number of contour edge segments in the second set of contour edge segments. This refers to the sequence number of the contour edge segment in the second contour edge segment set; According to the third contour edge segment set and width protection formula Define the width protection item; among which, For the width protection item, As the third weighting parameter, The total number of contour edge segments in the third contour edge segment set. The sequence number of the contour edge segment in the third contour edge segment set. To adjust parameters and satisfy , ; Based on the formula for the fourth contour edge segment set and density equalization term Determine the density equilibrium term; among which, For the density balance term, This is the fourth weighting parameter. The total number of low-density side contour edge segments in the fourth contour edge segment set. The sequence number of the low-density side contour edge segment in the fourth contour edge segment set; The total number of high-density side contour edge segments in the fourth contour edge segment set. The sequence number of the high-density side contour edge segment in the fourth contour edge segment set; These are constant parameters; Based on the basic optimization objective function, and taking at least one of the spacing balance term, the cooperative change term, the width protection term, and the density balance term as optimization compensation terms, the optimization objective function is constructed as follows: ;in, To optimize the calculated value of the objective function, Let be the basic optimization objective function.

6. The hotspot layout correction method in a mask layout as described in claim 5, characterized in that, The displacement of each contour edge segment is optimized according to the optimization objective function to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective, so as to determine the corrected layout of the hotspot map, including: With the constraints that the displacement is within a set displacement range, and the spacing parameter corresponding to each contour edge segment is not less than the minimum spacing, and the corresponding line width parameter is not less than the minimum line width, the displacement of each contour edge segment is optimized iteratively to obtain the corrected displacement corresponding to each contour edge segment that makes the calculated value of the optimization objective function reach the optimization objective.

7. The hotspot layout correction method in a mask layout as described in claim 5, characterized in that, After determining the revised hotspot map, the process also includes: The corrected pattern is subjected to exposure simulation to obtain a simulated exposure pattern; The consistency between the simulated exposure pattern and the hotspot pattern is verified. If the verification fails, the weighting coefficients of each item of the optimization objective function corresponding to each contour edge segment are adjusted, and the correction displacement corresponding to each contour edge segment is re-determined according to the updated optimization objective function to obtain the corrected pattern of the updated hotspot pattern.

8. A hotspot layout correction device in a mask layout, characterized in that, include: The hotspot determination module is used to determine the hotspot layout in the initial mask layout. The parameter calculation module is used to determine the environmental graphic parameters corresponding to each contour edge segment in the hotspot map based on the graphic information of the hotspot map. The function construction module is used to construct a basic optimization objective function with the displacement of the contour edge segment as the variable, based on the edge placement error that varies with the displacement of the contour edge segment. The function adjustment module is used to determine the optimization compensation term based on each of the environmental graphical parameters, and to superimpose the optimization compensation term and the basic optimization objective function to obtain the optimization objective function. An optimization calculation module is used to optimize the displacement of each contour edge segment according to the optimization objective function, and obtain the corrected displacement corresponding to each contour edge segment so that the calculated value of the optimization objective function reaches the optimization objective, so as to determine the corrected layout of the hotspot layout.

9. A hotspot layout correction device in a mask layout, characterized in that, include: Memory, used to store computer programs; A processor is configured to execute the computer program to implement the steps of the hotspot layout correction method in a mask layout as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that is executed to implement the steps of the hotspot layout correction method in a mask layout as described in any one of claims 1 to 7.

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